Question about relays

[scruffythewild]

Hello,

Having a hard time finding this on any forum. What gauge wire can be used as the trigger wire for a relay. The relay is powering my Hella lights which in total is 110W. I just want to know what I should fuse the low power wire running from the switch box to the relay at. Also how big should that "Low Power" wire be?

Thanks!

 

[shues]

Please understand that the wattage of the load passing through the normally-open and common contacts of your relay has no bearing on the gauge of the wire required for the relay coil, or the size of the fuse you should use to protect the wire.

The best way to determine the load presented by the relay coil is to use an ammeter in line with the relay coil. Unless the relay you are using is grossly oversized, I anticipate the load presented by the relay coil will be quite small. It should be well less than one amp.

 

[Jarred J.]

http://www.rattlebars.com/avalanche/relay_basics.html

usually its milliamps needed to activate a relay... 18 - 20 ga should be fine

 

[scruffythewild]

Thank you!!

Please understand that the wattage of the load passing through the normally-open and common contacts of your relay has no bearing on the gauge of the wire required for the relay coil, or the size of the fuse you should use to protect the wire.

The best way to determine the load presented by the relay coil is to use an ammeter in line with the relay coil. Unless the relay you are using is grossly oversized, I anticipate the load presented by the relay coil will be quite small. It should be well less than one amp.

http://www.rattlebars.com/avalanche/relay_basics.html

usually its milliamps needed to activate a relay... 18 - 20 ga should be fine

 

[wilsonbr90]

X2. I usually use 18ga and fuse appropriately at around 5 amps.

 

[JazzDad]

The missing factor in the equation is the length of the wire.

 

[Jarred J.]

but thats only TO the relay... the relay can be 2 inches from the switch...